Two brothers have appeared in court charged with ill treating and failing to prevent the suffering of horses in their care at Halswell and Kirwee, with some of the horses having to be euthanised.

Crown prosecutor Ben Vanderkolk told Christchurch District Court Judge Jane Farish and the jury that Douglas John Williamson and his brother John Blackwood Williamson, 47, had been given statutory notices about the care of the horses after the SPCA became concerned about the property.

They face 18 charges, ill treatment of one horse that had to be euthanised, wilful ill treatment of six more horses, five of which had to be euthanised, and 11 charges of failing to meet the behavioural and physical needs of horses.

Vanderkolk said when the SPCA went to the property in Quaifes Road, Halswell, in March 2010, they found an emaciated horse which could not get up and was crawling on its knees. It was in severe pain and distress and was shot where it was found.

They saw another older horse in a confined shed with no food and little water. It was "weaving" due to starvation, confinement, and boredom, Vanderkolk said.

Before that date the horses were getting inadequate feed and water, there was rubbish scattered around the property, poor fencing, and it was overstocked.

The brothers were given three separate statutory notices from October 2009 on what to do to improve the conditions for the horses. They were to supply supplementary feed, give them lice and worm treatment, remove hazards around the property, trim their hooves, reduce the number of horses, and supply more water troughs.

Hay was brought in, but no measures were effectively taken to reverse the deterioration of the horses, Vanderkolk said.

Some of the horses were taken off the property and hidden, but were later found in Kirwee.

On March 30, 2010, five horses were examined by a veterinarian and had to be euthanised as their condition had worsened since October. Their post-mortems showed they were starving, three had severe parasitic infestations, one had kidney lesions, and another had lung lesions.

Vanderkolk said the brothers knew what they were doing. The wilful ill treatment of the horses was no accident as they had been told how to improve the conditions, which they ignored.

The horses were seized, put on a holding property, and were fostered out, he said.

Defence counsel for Douglas Williamson, Colin Eason, said it was a sad case and no-one involved did not have some sympathy for the horses.

He said the jury would have to be sure about what caused the horses to be unwell - if it was neglect and ill treatment, or something else as some of the horses were healthy.

Douglas Williamson was not the person whose acts contributed to the situation that arose, he said.

Keith Owens, for John Williamson, said there was no ill treatment or wilful ill treatment of any horses by the accused.